A005312 Maximal sum of inverse squares of the singular values of symmetric anti-Hadamard matrices of order n.

1, 3, 7, 16, 46, 138, 624

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• hard
• more

References

• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Noga Alon and Van H. Vu, Anti-Hadamard Matrices, Coin Weighing, Threshold Gates, and Indecomposable Hypergraphs, Journal of Combinatorial Theory, Series A, Volume 79, Issue 1, July 1997, Pages 133-160.
• R. L. Graham and N. J. A. Sloane, Anti-Hadamard matrices, Linear Alg. Applic., 62 (1984), 113-137, Table 1.

Crossrefs

Cf. A005313.

Extensions

Definition corrected by Stefano Spezia, Jan 30 2022

a(7) confirmed and inserted by Stefano Spezia, Feb 20 2022